The long-term objective is to explore mechanisms regulating protein synthesis in the liver of the normal animals and to investigate deviations of the control mechanism in malignant liver cells. Specific emphasis is placed on the role of amino acid supply and hormones in regulating synthesis of protein by normal liver cells and by malignant liver cells. In the current and ensuing year, the role of amino acid supply on RNA synthesis in liver nuclei and liver mitochondria continues to be examined. The effect of malignancy on formation of liver ferritin is being examined to determine how the change in form (isoproteins) occur in malignancy.